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1.
Photochem Photobiol Sci ; 17(4): 482-490, 2018 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-29582862

RESUMEN

Leishmaniasis is a neglected disease present in more than 88 countries. The currently adopted chemotherapy faces challenges related to side effects and the development of resistance. Photodynamic therapy (PDT) is emerging as a therapeutic modality for cutaneous leishmaniasis. Zn(ii) meso-tetrakis(N-ethylpyridinium-2-yl)porphyrin (ZnTE-2-PyP4+, ZnP) is a cationic, water-soluble, zinc porphyrin-based photosensitizer whose photodynamic effect on Leishmania braziliensis was analyzed by evaluating the number of visibly undamaged and motile cells, cell membrane integrity, mitochondrial membrane potential, and ultrastructural damage. Treatment of parasites with ZnP and light induced damage in up to 90% of L. braziliensis promastigote cells. Propidium iodide labeling suggested the loss of plasma membrane integrity. In samples treated with ZnP and light, a hyperpolarization of the mitochondrial membrane potential was also observed. Ultrastructural evaluation of promastigotes after photodynamic treatment indicated a loss of cytoplasmic material and the presence of vacuoles. Scanning electron microscopy showed wrinkling of the plasma membrane and a reduced cell volume. Additionally, the number of amastigotes per macrophage was reduced by about 40% after photodynamic application. The treatment showed no considerable toxicity against mammalian cells. Therefore, the results indicated that PDT associated with ZnTE-2-PyP4+ represents a promising alternative to cutaneous leishmaniasis treatment.


Asunto(s)
Antiparasitarios/farmacología , Leishmania braziliensis/efectos de los fármacos , Leishmania braziliensis/crecimiento & desarrollo , Leishmaniasis Cutánea/parasitología , Metaloporfirinas/farmacología , Fotoquimioterapia , Fármacos Fotosensibilizantes/farmacología , Antiparasitarios/química , Humanos , Leishmaniasis Cutánea/tratamiento farmacológico , Metaloporfirinas/química , Microscopía Electrónica de Rastreo , Pruebas de Sensibilidad Parasitaria , Fármacos Fotosensibilizantes/química
2.
Biochim Biophys Acta Gen Subj ; 1862(3): 427-439, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29126854

RESUMEN

BACKGROUND: Quantum dots (QDs) are outstanding nanomaterials of great interest to life sciences. Their conjugation versatility added to unique optical properties, highlight these nanocrystals as very promising fluorescent probes. Among uncountable new nanosystems, in the last years, QDs conjugated to glycans or lectins have aroused a growing attention and their application as a tool to study biological and functional properties has increased. SCOPE OF REVIEW: This review describes the strategies, reported in the literature, to conjugate QDs to lectins or carbohydrates, providing valuable information for the elaboration, improvement, and application of these nanoconjugates. It also presents the main applications of these nanosystems in glycobiology, such as their potential to study microorganisms, the development of diseases such as cancer, as well as to develop biosensors. MAJOR CONCLUSIONS: The development of glyconanoparticles based on QDs emerged in the last decade. Many works reporting the conjugation of QDs with carbohydrates and lectins have been published, using different strategies and reagents. These bioconjugates enabled studies that are very sensitive and specific, with potential to detect and elucidate the glycocode expressed in various normal or pathologic conditions. GENERAL SIGNIFICANCE: Produce a quick reference source over the main advances reached in the glyconanotechnology using QDs as fluorescent probes.


Asunto(s)
Glicoconjugados , Nanotecnología/métodos , Puntos Cuánticos , Técnicas Bacteriológicas , Técnicas Biosensibles , Metabolismo de los Hidratos de Carbono , Carbohidratos/análisis , Línea Celular Tumoral , Técnicas de Química Analítica/métodos , Fluorescencia , Glicoconjugados/administración & dosificación , Glicoconjugados/química , Glicoconjugados/uso terapéutico , Humanos , Lectinas/administración & dosificación , Lectinas/química , Nanopartículas del Metal , Modelos Moleculares , Micología/métodos , Nanotecnología/tendencias , Neoplasias/química , Neoplasias/diagnóstico , Imagen Óptica/métodos , Parasitología/métodos , Puntos Cuánticos/administración & dosificación , Puntos Cuánticos/química , Puntos Cuánticos/uso terapéutico
3.
Sleep Med ; 16(9): 1156-9, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26298794

RESUMEN

BACKGROUND: Restless Legs Syndrome (RLS) or Willis-Ekbom Disease (WED) is highly prevalent, but patients and healthcare providers alike know little about it. Furthermore, controversy persists as to the best way of diagnosing this nosological entity. OBJECTIVE: To verify whether the term used to refer to this disease entity (Restless Legs Syndrome or Willis-Ekbom Disease) affects the prevalence of self-diagnosed RLS/WED in a sample of newly graduated physicians. METHODS: Newly graduated physicians were asked to self-evaluate for the presence of RLS/WED. Briefly, participants were allocated randomly across two groups. One was asked to self-assess for RLS, while the other was asked to self-assess for WED. The evaluation form given to one group asked 'Do you have Restless Legs Syndrome?' whereas the form given to participants in the other group asked 'Do you have Willis-Ekbom Disease?'. Both forms also contained the four criteria for diagnosing RLS proposed by the International Restless Legs Syndrome Study Group (IRLSSG) and instructions for self-diagnosis according to these criteria. RESULTS: The study sample comprised 1413 newly graduated physicians. Of the 708 participants who were given the form that used the term RLS, 87 (12.28%) diagnosed themselves with the condition. Conversely, of 705 physicians given the form with the term WED, 13 (1.84%) diagnosed themselves with the condition (p <0.0001). CONCLUSION: A greater proportion of newly graduated physicians diagnosed themselves with RLS/WED when presented with the term Restless Legs Syndrome than when presented with the term Willis-Ekbom Disease. This suggests that the term Restless Legs Syndrome may not be the most appropriate term to denote this nosological entity.


Asunto(s)
Internado y Residencia , Síndrome de las Piernas Inquietas/diagnóstico , Adulto , Brasil , Competencia Clínica , Diagnóstico Diferencial , Autoevaluación Diagnóstica , Femenino , Humanos , Masculino , Prevalencia , Síndrome de las Piernas Inquietas/epidemiología , Síndrome de las Piernas Inquietas/psicología , Adulto Joven
4.
Spinal Cord ; 53(12): 875-6, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26123211

RESUMEN

STUDY DESIGN: One case report of proximal tibia fracture in a patient with incomplete spinal cord injury (SCI) associated with robotic treadmill training. OBJECTIVE: To raise the awareness that bone densitometry may be recommended before starting the robotic treadmill therapy, as well as the active vigilance of symptoms after therapy. SETTING: Institute of Physical and Rehabilitation Medicine, Lucy Montoro Institute for Rehabilitation, Hospital das Clínicas, School of Medicine, University of São Paulo, São Paulo, Brazil. CASE REPORT: The patient, female gender, with a fracture of vertebra T12 and arthrodesis from T9 to L1 (American Spinal Injury Association Classification (ASIA-C)). Training on Lokomat consisted of five 30-min weekly sessions, under the supervision of a qualified professional. At the beginning of the 19th session, the patient complained of pain in the anterior region of the left knee. Lokomat and any other body support therapy were discontinued. Magnetic resonance imaging (MRI) evidenced a transverse, oblique, metaphyseal proximal anterior and medial tibial fracture. CONCLUSION: Fractures are among the chronic complications of a SCI, affecting 34% and many times arising from minimal traumas. Lokomat resembles physiological walking, and more studies show its benefits. Many studies encourage the use of robotic devices for the rehabilitation of lower limbs, but there are still several unanswered questions. However, there are not enough studies to show whether there is a higher risk of fracture incidence in patients with osteopenia or osteoporosis who trained on the Lokomat.


Asunto(s)
Terapia por Ejercicio/efectos adversos , Fracturas Óseas/etiología , Robótica , Traumatismos de la Médula Espinal/rehabilitación , Tibia/patología , Adulto , Femenino , Fracturas Óseas/diagnóstico , Humanos , Imagen por Resonancia Magnética
5.
Genet Mol Res ; 14(4): 18452-64, 2015 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-26782493

RESUMEN

The worldwide obesity pandemic requires the use of anti-obesity drugs. Sibutramine is an anti-obesity drug that has been used worldwide but is indiscriminately consumed in Brazil. Several studies have demonstrated that sibutramine promotes weight loss and weight maintenance, but several side effects have been associated with its systematic consumption. For this reason, sibutramine was withdrawn from the European and American markets, but still remains legal for use in Brazil. Studies have shown that a 5-10% reduction in body weight results in outstanding health benefits for obese patients. However, in order to promote significant weight loss, it is necessary to use sibutramine for at least 2 years. This long-term exposure has carcinogenic potential, as sibutramine causes DNA damage. Thus, this study evaluated the in vivo mutagenic potential of sibutramine alone (5, 7, 10, 15, and 20 mg/kg) and in association with Spirulina maxima (150 and 300 mg/kg), a cyanobacterium with antioxidant potential, using the polychromatic erythrocyte micronucleus test. Our results reinforced the mutagenic potential of sibutramine alone, which showed a time-dependent action. Combinatory treatments with S. maxima were not able to reduce the genotoxicity of sibutramine. These results were confirmed in vitro with the cytokinesis-blocked micronucleus test. In conclusion, our data showed that new alternative anti-obesity treatments are needed since the consumption of sibutramine can increase the risk of cancer in overweight patients.


Asunto(s)
Depresores del Apetito/farmacocinética , Ciclobutanos/farmacología , Mutágenos/farmacología , Spirulina/fisiología , Adolescente , Adulto , Fármacos Antiobesidad/farmacología , Fármacos Antiobesidad/toxicidad , Depresores del Apetito/administración & dosificación , Depresores del Apetito/toxicidad , Brasil , Ciclobutanos/administración & dosificación , Ciclobutanos/toxicidad , Femenino , Humanos , Linfocitos/efectos de los fármacos , Linfocitos/metabolismo , Masculino , Micronúcleos con Defecto Cromosómico/efectos de los fármacos , Pruebas de Micronúcleos , Mutágenos/administración & dosificación , Mutágenos/toxicidad , Reticulocitos/efectos de los fármacos , Reticulocitos/metabolismo , Adulto Joven
6.
Arq. bras. med. vet. zootec ; 65(5): 1383-1388, out. 2013. tab
Artículo en Portugués | LILACS | ID: lil-689755

RESUMEN

O presente estudo teve como objetivo promover o levantamento de índices zootécnicos para calcular e comparar a eficiência reprodutiva de rebanhos bovinos leiteiros por diferentes métodos. O intervalo de partos dos rebanhos estudados apresentou uma variação de 13,3 a 15,2 meses por meio dos diferentes métodos utilizados para sua obtenção, não se observando diferença significativa (P>0,05) entre eles. As avaliações pelos métodos de Johnson et al. (1964) e Butendieck et al. (1972) mostraram, respectivamente, eficiência reprodutiva de 79,5 e 77,8%. Embora considerados métodos mais eficientes que o de Willcox et al. (1957), cuja média encontrada para os mesmos rebanhos foi de 90,2%, não se observou diferença significativa entre os resultados obtidos pelos três métodos.


The study aimed to promote the lifting of indexes to calculate and compare the reproductive efficiency of dairy cattle herds by different methods. The parturition interval studied showed a variation from 13.3 to 15.2 months by means of different methods for obtaining it are not observing a significant difference (P> 0.05) between them. Evaluations by the methods of Johnson et al (1964) and Butendieck et al. (1972) showed, respectively, reproductive efficiency of 79.5 and 77.8%. Although regarded as the most efficient methods of Willcox et al. (1957), whose average found in the same herd was 90.2%, there was no significant difference between the results obtained by three methods.


Asunto(s)
Animales , Bovinos , Bovinos/anatomía & histología , Bovinos/crecimiento & desarrollo , Técnicas Reproductivas , Técnicas Reproductivas/veterinaria
7.
Hum Exp Toxicol ; 32(8): 837-45, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23632007

RESUMEN

A method of extracting membranes from red blood cells (RBCs) is described, which were in turn used to assay acetylcholinesterase (AChE) activity. The evidence for the enzyme activity was established by selective inhibition using 1,5-bis(4-allyldimethylammoniumphenyl) pentan-3-one dibromide, tetraisopropyl pyrophosphoramide and neostigmine. Blood samples were exposed to three organophosphorus (dichlorvos, chlorpyrifos and diazinon) and two carbamate (carbaryl and carbofuran) pesticides. Afterwards AChE activities in RBC membranes were determined. The concentrations capable to inhibit the enzyme activity by 50% (IC50) for the pesticides were 10.66 µM (dichlorvos), 21.42 µM (chlorpyrifos), 109.98 µM (carbaryl) and 5.44 µM (carbofuran). The results related to 20% enzyme inhibition (level used in the estimation of threshold limits for anticholinesterase compounds) were below those acceptable daily intake values enacted by relevant national and international regulations. These results suggest that the proposed AChE extraction from RBC and assay could be a suitable method for monitoring occupational exposure to pesticides.


Asunto(s)
Acetilcolinesterasa/metabolismo , Bioensayo/métodos , Inhibidores de la Colinesterasa/toxicidad , Eritrocitos/efectos de los fármacos , Plaguicidas/toxicidad , Células Cultivadas , Eritrocitos/enzimología , Humanos
8.
Braz J Med Biol Res ; 44(4): 311-8, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21344137

RESUMEN

The antischistosomal activity of the sulfated polysaccharide α-D-glucan (Glu.SO(4)) extracted from Ramalina celastri was evaluated after encapsulation into liposomes (Glu.SO(4)-LIPO) in Schistosoma mansoni-infected mice. The effect of treatment with Glu.SO(4) and Glu.SO(4)-LIPO (10 mg/kg) on egg elimination, worm burden and hepatic granuloma formation was assessed using female albino Swiss mice, 35-40 days of age, weighing 25 ± 2 g, infected with 150 cercariae/animal (Biomphalaria glabrata, BH strain). Four groups (N = 10) were studied, two controls (empty liposomes and NaCl) and two treated groups (Glu.SO(4)-LIPO and Glu.SO(4)) using a single dose. Parasitological analysis revealed that Glu.SO(4)-LIPO was as efficient as Glu.SO(4) in reducing egg elimination and worm burden. Treatment with free Glu.SO(4) and Glu.SO(4)-LIPO induced a statistically significant reduction in the number of granulomas (62 and 63%, respectively). Lectin histochemistry showed that wheat germ agglutinin intensely stained the egg-granuloma system in all treated groups. On the other hand, peanut agglutinin stained cells in the control groups, but not in the treated groups. The present results suggest a correlation between the decreasing number of hepatic egg-granulomas and the glycosylation profile of the egg-granuloma system in animals treated with free Glu.SO(4) or Glu.SO(4)-LIPO.


Asunto(s)
Antihelmínticos/farmacología , Glucanos/farmacología , Líquenes/química , Extractos Vegetales/farmacología , Schistosoma mansoni/efectos de los fármacos , Esquistosomiasis mansoni/tratamiento farmacológico , Animales , Antihelmínticos/administración & dosificación , Heces/parasitología , Femenino , Glucanos/administración & dosificación , Glucanos/aislamiento & purificación , Inmunohistoquímica , Intestinos/parasitología , Intestinos/patología , Liposomas , Hígado/parasitología , Hígado/patología , Masculino , Ratones , Extractos Vegetales/administración & dosificación
9.
Arq. bras. med. vet. zootec ; 62(5): 1263-1266, out. 2010.
Artículo en Inglés | LILACS | ID: lil-570489

RESUMEN

Descrevem-se as doenças gástricas de avestruzes diagnosticadas em um Laboratório de Doenças das Aves, Belo Horizonte-MG, entre 1997 e 2009. As afecções gástricas corresponderam a 46,2% de todos os casos de doença, com quadros que incluíram impactação (83,3%), infecções e parasitoses (16,7%). As impactações foram causadas por material não alimentar diversificado e as infecções e parasitoses incluíram o fungo Macrorhabdus ornithogaster (megabacteria) e o nematódeo Libyostrongylus douglassii.


Asunto(s)
Animales , Técnicas de Laboratorio Clínico , Enfermedades Gastrointestinales/etiología , Enfermedades Gastrointestinales/prevención & control , Enfermedades Gastrointestinales/veterinaria , Struthioniformes/parasitología
10.
Arq. bras. med. vet. zootec ; 59(1): 242-245, fev. 2007.
Artículo en Portugués | LILACS | ID: lil-456443

RESUMEN

The research was accomplished in eight dairy water buffalo herds, randomically choosen in Região do Alto São Francisco, State of Minas Gerais, Brazil. Information was collected from March to November, 2003 during 270 days of observation. In order to determine the somatic cell count (SCC) in presence or absence of microbial isolation, 1,393 samples were collected from 285 lactating females and microbiological exams and SCC were done. Samples obtained from udders without evidence of clinical or subclinical inflammation showed infection for a great variety of microbial mastitis pathogens. The low SCC did not necessarily indicate the absence of intramammary infection, suggesting that SCC patterns used for bovine cannot be appropriate in order to control mastitis in buffalo herds.


Asunto(s)
Búfalos , Bacterias Grampositivas/aislamiento & purificación , Recuento de Células/métodos , Leche/microbiología , Mastitis/diagnóstico , Mastitis/microbiología , Staphylococcus aureus/aislamiento & purificación
11.
Oral Dis ; 13(1): 105-9, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17241439

RESUMEN

AIM: To assess the prevalence of persistent oral malodour in a general population in Rio de Janeiro and to find out whether sex and age are risk factors for this condition. METHODS: This was a cross-sectional survey in which university students (informants) were interviewed regarding the prevalence of persistent oral malodour in their households. To estimate the effects of sex and age logistic regression models with and without random effects for the informant were applied. RESULTS: The prevalence of persistent oral malodour was 15% (95% confidence interval: 11-19). The risk of persistent malodour was nearly three times higher in men than in women, regardless of age. The risk was slightly more than three times higher in people over 20 years of age compared with those aged 20 years or under, controlling for sex. CONCLUSIONS: Oral malodour is common in Rio de Janeiro, more prevalent in men and in those over 20 years of age, in both sexes. CLINICAL RELEVANCE OF THE FINDINGS: Freedom from disabling oral malodour is an outcome indicator of social well-being. Health professionals in general, and dentists in particular, should be trained to appropriately manage and treat people who suffer from persistent oral malodour.


Asunto(s)
Halitosis/epidemiología , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Brasil/epidemiología , Niño , Preescolar , Estudios Transversales , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Factores Sexuales , Salud Urbana/estadística & datos numéricos
12.
Biomarkers ; 11(5): 480-4, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16966164

RESUMEN

Cell differentiation/dedifferentiation includes changes in oligosaccharide composition and distribution in the cell surface glycoconjugates. Lectins have been used as auxiliary tools in histopathological diagnosis of mammary, uterus and brain pathologies. Acridinium ester (AE) conjugated to biomolecules has been employed in chemiluminescent analytical applications. This work aimed to use a lectin, concanavalin A (Con A), conjugated to AE as a chemiluminescent histochemistry tool. Biopsies of normal and infiltrating duct carcinoma (IDC) of mammary tissues were treated by a Con A-AE derivative. Photon emission, observed during the breakage of the chemical bound between Con A and AE, was quantified, expressed in relative light units (RLU) and correlated to the labelling of the normal and transformed tissues. The results demonstrated that RLU presented a linear relationship with the labelled tissue area in the range 0.125-1.0 cm2 (r=0.98). Furthermore, RLU was much higher for the IDC (1283.920x103+/-220.621x103) than the normal tissue (2.565x103+/-0.247x103), namely, about 500 times higher. The Con A-AE conjugation efficiency, differential staining of normal and IDC tissues, and quantification of results contribute to a decrease in the subjectivity in routine histopathological diagnoses and indicate that acrydinum ester can join other lectin marker to be used in histochemistry.


Asunto(s)
Acridinas/química , Biomarcadores de Tumor/análisis , Neoplasias de la Mama/química , Mama/química , Lectinas/química , Humanos , Luminiscencia
13.
Arq. neuropsiquiatr ; 63(3B): 761-765, set. 2005. tab, ilus, graf
Artículo en Inglés | LILACS | ID: lil-445150

RESUMEN

CONTEXT: Sleep has an important function in the physical and emotional development of children. Some studies suggest an association between impulsivity and sleep disorders. However, little is known about this association in schoolchildren aged 8 to 10 years. METHOD: We studied 1180 children, 547 with sleep disorders (SD) and 633 without SD (control group), classified with SD questionnaires. Within the SD group, 53 children with sleep-related respiratory disorders (SRRD) and 521 children with non-respiratory sleep disorders (NRSD) were analyzed. We assessed emotional indicators of impulsivity with Bender test. RESULTS: More SD children presented impulsivity than control group (p<0.05). More NRSD and 10 years old children presented impulsivity than control group of the same age (p=0.001). Impulsivity and SRRD were associated with 8 years old children (p<0.05). CONCLUSION: Children with SD, 8 years old children with SRRD, and 10 years old children with NRSD presented higher proportion of impulsivity than control children.


CONTEXTO: O sono tem função importante no desenvolvimento físico e emocional das crianças. Alguns estudos sugerem a associação de impulsividade e distúrbios do sono, sendo pouco conhecida esta associação em escolares na faixa etária de 8 a 10 anos. MÉTODO: Estudamos 1180 crianças, 547 com distúrbio do sono (DS) e 633 normais (grupo controle), classificadas através de questionários sobre distúrbios do sono. Dentro do grupo DS, analisamos separadamente as crianças com distúrbio respiratório relacionado ao sono (DRRS) e com distúrbios não respiratórios do sono (DNRS). Aplicamos o Teste Gestáltico de Bender (TB) para detectar os indicadores emocionais de impulsividade. RESULTADOS: Maior número de crianças com DS apresentaram impulsividade em relação às crianças do grupo controle (p<0,05). Mais crianças de 10 anos de idade do grupo DNRS apresentaram impulsividade em relação ao grupo controle da mesma idade (p=0,001). Impulsividade e DRRS estiveram associados apenas entre as crianças de 8 anos de idade (p<0,05). CONCLUSÃO: Crianças com DS em geral, crianças com DRRS de 8 anos de idade, e crianças com 10 anos de idade do grupo DNRS apresentaram maior proporção de indicadores de impulsividade do que crianças do grupo controle.


Asunto(s)
Niño , Femenino , Humanos , Masculino , Conducta Impulsiva/psicología , Trastornos del Sueño-Vigilia/psicología , Factores de Edad , Prueba de Bender-Gestalt , Brasil/epidemiología , Conducta Impulsiva/epidemiología , Métodos Epidemiológicos , Distribución por Sexo , Trastornos del Sueño-Vigilia/clasificación
14.
Braz J Med Biol Res ; 37(3): 301-5, 2004 03.
Artículo en Inglés | MEDLINE | ID: mdl-15060694

RESUMEN

Xylofucoglucuronan from Spatoglossum schröederi algae was tested as a support for antibiotic immobilization. The polysaccharide (20 mg in 6 ml) was first activated using carbodiimide, 1-ethyl-3-(3-dimethylamino-propyl)carbodiimide methiodide (20 mg in 2 ml), under stirring for 1 h at 25 masculine C and pH from 4.5 to 5.0. After adjusting the pH to 8.0, either gentamicin or amikacin (62.5 mg in 1.25 ml) was then immobilized on this chemically modified polysaccharide with shaking for 24 h in a cold room. Infrared spectra of the activated carbodiimide xylofucoglucuronan showed two bands to carbonyl (C=O at 1647.9 and 1700.7 cm(-1)) and to amide (C-NH2) groups (1662.8 and 1714.0 cm(-1)). Microbial characterization of the derivatives was carried out by the disk diffusion method using Staphylococcus aureus or Klebsiella pneumoniae incorporated in Müller Hinton medium. Inhibition halos of bacterial growth were observed for the antibiotics immobilized on this sulfated heteropolysaccharide before and after dialysis. However, the halos resulting from the samples after dialysis were much smaller, suggesting that dialysis removed either non-covalently bound antibiotic or other small molecules. In contrast, bacterial growth was not inhibited by either xylofucoglucuronan or its activated form or by gentamicin or amikacin after dialysis. An additional experiment was carried out which demonstrated that the sulfated heteropolysaccharide was hydrolyzed by the microorganism. Therefore, the antibiotic immobilized on xylofucoglucuronan can be proposed as a controlled drug delivery system. Furthermore, this sulfated heteropolysaccharide can be extracted easily from sea algae Spatoglossum schröederi.


Asunto(s)
Amicacina/farmacología , Antibacterianos/farmacología , Gentamicinas/farmacología , Klebsiella/efectos de los fármacos , Phaeophyceae/química , Polisacáridos , Staphylococcus aureus/efectos de los fármacos , Amicacina/síntesis química , Antibacterianos/síntesis química , Diálisis , Difusión , Gentamicinas/síntesis química , Pruebas de Sensibilidad Microbiana , Solubilidad
15.
Biomaterials ; 24(26): 4777-83, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-14530075

RESUMEN

Heparin, a well-known anticoagulant, has been frequently used to coat surfaces for attaining blood compatibility of polymeric materials. Since carbodiimides are often used for immobilization of heparin on these biomaterials, the present study intended to evaluate some properties of carbodiimide-treated heparin. It was observed that the properties of heparin were altered after treatment with carbodiimide, mainly in the molar excess of this reagent. Thus, dye fixation and electrophoretic behaviour of heparin were modified, as well as its degradability by specific enzymes. Also, these modifications resulted in loss of anticoagulant activity. Infrared spectra of this carbodiimide-treated heparin presented evidence that can confirm its modification.


Asunto(s)
Coagulación Sanguínea/efectos de los fármacos , Carbodiimidas/química , Carbodiimidas/farmacología , Liasa de Heparina/química , Heparina/química , Heparina/farmacología , Polisacárido Liasas/química , Espectrofotometría Infrarroja/métodos , Bioensayo
16.
Eur J Histochem ; 47(2): 139-42, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12777210

RESUMEN

Lectins have been intensively used in histochemical techniques for cell surface characterization. These proteins are involved in several biological processes and their use as histochemical markers have been evaluated since they can indicate differences in cell surfaces. Parkia pendula lectin (PpeL) was evaluated as histochemical marker for meningothelial meningioma biopsies. Tissue slices were incubated with PpeL conjugated to horseradish peroxidase (PpeL-HRP) and Concanavalin A-HRP (ConA-HPR) and the binding visualized with diaminobenzidine and hydrogen peroxide. The lectin-tissue binding was inhibited with D-glucose. PpeL showed to be a useful tool for the characterization of meningothelial tumour and clinico-pathological diagnosis.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Neoplasias Meníngeas/metabolismo , Meningioma/metabolismo , Lectinas de Plantas/metabolismo , Adulto , Peroxidasa de Rábano Silvestre/química , Humanos , Técnicas para Inmunoenzimas , Neoplasias Meníngeas/patología , Meningioma/patología , Persona de Mediana Edad , Lectinas de Plantas/química
17.
Braz J Med Biol Res ; 35(4): 459-63, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11960195

RESUMEN

We developed an efficient method to prepare a hybrid inorganic-organic composite based on polyvinyl alcohol (PVA) and polysiloxane using the sol-gel disc technique. Antigen obtained from Yersinia pestis was covalently immobilized onto these discs with glutaraldehyde and used as solid phase in ELISA for antibody detection in serum of rabbits experimentally immunized with plague. Using 1.25 microg antigen per disc, a peroxidase conjugate dilution of 1:4,000 and a serum dilution of 1:200 were adequate for the establishment of the procedure. These values are similar to those used for PVA-glutaraldehyde discs, plasticized filter paper discs and the polyaniline-Dacron composite discs. This procedure is comparable to that which utilizes the adsorption of the antigen to conventional PVC plates, with the amount of antigen being one fourth that employed in conventional PVC plates (5 microg/well). In addition to the performance of the polysiloxane/PVA-glutaraldehyde disc as a matrix for immunodetection, its easy synthesis and low cost are additional advantages for commercial application.


Asunto(s)
Antígenos Bacterianos/aislamiento & purificación , Ensayo de Inmunoadsorción Enzimática/métodos , Alcohol Polivinílico/química , Siloxanos/química , Yersinia/inmunología , Animales , Ensayo de Inmunoadsorción Enzimática/instrumentación , Fijadores , Glutaral , Conejos
18.
J Biomed Mater Res ; 56(2): 257-60, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11340597

RESUMEN

Polyaniline (PANI) was chemically synthesized on a dacron disk surface and an antigen (F1 fraction) obtained from Yersinia pestis was covalently fixed onto this composite via glutaraldehyde. The enzyme linked immunosorbent assay (ELISA) or rapid ELISA procedure detected immunoglobulin G (IgG) anti-F1 fraction in human serum employing this derivative. The appropriate conditions for carrying out the test were established as an antigen concentration of 2 microg/PANI-dacron disk, peroxidase labeled goat anti-human IgG conjugate diluted 4000 times, and a serum dilution of 1:100. The PANI-dacron disks showed greater antigen retention than conventional poly(vinyl chloride) plates and less antibody unspecific adsorption.


Asunto(s)
Compuestos de Anilina , Anticuerpos Antibacterianos/análisis , Proteínas Bacterianas/inmunología , Ensayo de Inmunoadsorción Enzimática , Peste/inmunología , Tereftalatos Polietilenos , Yersinia pestis/inmunología , Compuestos de Anilina/síntesis química , Compuestos de Anilina/química , Proteínas Bacterianas/sangre , Materiales Biocompatibles Revestidos , Estabilidad de Medicamentos , Resinas Epoxi , Humanos , Tereftalatos Polietilenos/química , Polietilenos , Factores de Tiempo
19.
Braz J Med Biol Res ; 33(7): 823-7, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10881058

RESUMEN

F1-antigen purified from Yersinia pestis was covalently linked to 5-mm diameter filter paper discs plasticized with polyvinyl alcohol-glutaraldehyde. These discs were used both for ELISA and dot-ELISA for the detection of anti-F1 IgG in rabbits. The best conditions were achieved using 1.25 microg of F1 antigen/disc, 3% w/v skim milk in PBS as blocking agent, anti-IgG peroxidase conjugate diluted 12,000 times, and serum from rabbits immunized or not against Y. pestis, diluted 6,400 times. The absorbance values obtained from the comparative study between this procedure and conventional ELISA were not significantly different but the low cost of the reagents employed in ELISA using the filter paper discs plasticized with polyvinyl alcohol-glutaraldehyde makes this method economically attractive.


Asunto(s)
Anticuerpos Antibacterianos/aislamiento & purificación , Ensayo de Inmunoadsorción Enzimática/instrumentación , Peste/inmunología , Alcohol Polivinílico/química , Yersinia pestis/inmunología , Animales , Anticuerpos Antibacterianos/sangre , Antígenos Bacterianos/sangre , Antígenos Bacterianos/inmunología , Ensayo de Inmunoadsorción Enzimática/economía , Filtración/instrumentación , Cabras , Conejos
20.
Mem Inst Oswaldo Cruz ; 95(1): 95-6, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10656712

RESUMEN

Antigen from Yersinia pestis was adsorbed on cellulose acetate discs (0.5 cm of diameter) which were obtained from dialysis membrane by using a paper punch. ELISA for human plague diagnosis was carried out employing this matrix and was capable to detect amount of 1.3 microg of antigen, 3,200 times diluted positive serum using human anti-IgG conjugate diluted 1:4,000. No relevant antigen lixiviation from the cellulose acetate was observed even after washing the discs 15 times. The discs were impregnated by the coloured products from the ELISA development allowing its use in dot-ELISA. Furthermore, cellulose acetate showed a better performance than the conventional PVC plates.


Asunto(s)
Antígenos Bacterianos/aislamiento & purificación , Celulosa , Ensayo de Inmunoadsorción Enzimática/métodos , Peste/inmunología , Yersinia pestis/inmunología , Humanos , Inmunoglobulina G/aislamiento & purificación , Volumetría
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